Building window wiper



FIG. 1 is an elevational view of a building window wiper illustrating my invention;

FIG. 2 is a view from the opposite side of FIG. 1;

FIG. 3 is a view of the right side of FIG. 1, the opposite side being a mirror image thereof;

FIG. 4 is view of the top side of FIG. 1; and,

FIG. 5 is a view of the bottom side of FIG. 1. 

The ornamental design for a building window wiper, as shown and described. 